CN108700439B

CN108700439B - Product detector

Info

Publication number: CN108700439B
Application number: CN201680081971.0A
Authority: CN
Inventors: 斯蒂芬·盖伊特
Original assignee: Canada To Bosimai Ltd
Current assignee: Canada To Bosimai Ltd
Priority date: 2016-02-19
Filing date: 2016-02-19
Publication date: 2021-07-13
Anticipated expiration: 2036-02-19
Also published as: CA3014507C; US11111082B2; BR112018016772A2; EP3417249B1; EP3417249A1; EP3417249A4; WO2017141066A1; CN108700439A; HUE059320T2; CA3014507A1; US20200283237A1

Abstract

The invention provides a detector (1) for detecting a product flow on a conveyor (2), the detector comprising: a base (3) fixed to a side of the conveyor (2); a pendulum (4) rotationally fixed to the base (3) about an axis (5), said pendulum (4) rotating when the product abuts against it; and the sensor (6) is used for detecting the position of the pendulum-shaped member (4). The detector is characterized in that the pendulum (4) comprises at its end a contact member (7) having the shape of a flat plate, wherein the non-metallic surface is intended to contact the product.

Description

Product detector

Technical Field

The invention belongs to the field of product conveying in industrial processing lines. The object of the invention is a product detector.

Background

In the field of the invention, products such as bottles or cans are conveyed by means of an endless belt conveyor on which the bottles or cans stand. The conveyor has two opposite lateral vertical side walls between which the products move. The speed of these conveyors is adjusted for controlling the entire line process and, therefore, it is necessary to detect the presence or absence of products in predefined fixed areas.

The result of this detection is then used as input data to control the movement of the conveyor.

For example, DE102010000596 discloses a product detector. Such a metal detector is mounted beside the conveyor, fixed to the conveyor support by means of a base. The detector has a pendulum which is free to rotate about an axis parallel to the transport direction. A longitudinal bar is mounted at the end of this pendulum for contacting the product.

The longitudinal bars extend above the conveying surface when no product is present. When products are present, they push the pendulums back behind the vertical wall of the conveyor by acting on the longitudinal bars. The position of the pendulum is detected by a metal sensing member. Thus, the longitudinal bars will pass the vertical side edges of the conveyor.

Under normal production conditions, the longitudinal metal bars are constantly in contact with the product stream. This creates problems for sensitive products such as cans, metal bottles or any other kind of product that has not undergone a post surface treatment such as labeling: the metal longitudinal bars scratch the surface and may accumulate dust and particles which are then transferred to the product. Accordingly, there is a need in the industry for a product detector that does not cause damage to the surface of the product being detected.

Furthermore, since the longitudinal bars have to pass the vertical side edges of the conveyor, it is not suitable to add only soft protection around the longitudinal bars, since the openings required in this edge would be too large and allow the passage of undesirable particles such as cullet.

Some non-contact detectors have also been proposed for detecting metal cans or products. However, such detectors are not compatible with glass products, which cannot be detected using the same electromagnetic principles.

The present invention therefore aims to improve the state of the art as described above by proposing a product detector that is compatible with both metallic and non-metallic products, does not cause damage to the outer surface of the products, and/or is compatible with small apertures in the transverse walls of the conveyor.

Disclosure of Invention

To achieve this object, the invention proposes a detector with a contact member in the shape of a flat piece with a soft contact surface (preferably based on plastic).

According to the present invention there is provided a detector for detecting product flow on a conveyor, the detector comprising: a base fixed to a side of the conveyor; a pendulum fixed to the base, rotating about an axis, the pendulum rotating when a product abuts against it; a sensor for detecting a position of the pendulum.

This detector is characterized in that the pendulum comprises at its end a contact member having the shape of a flat plate, wherein the non-metallic surface is intended to contact the product.

Drawings

Further characteristics and advantages of the invention will be better understood from the following description of preferred embodiments, given by way of non-limiting illustration, with reference to the attached drawings, in which:

figures 1 to 8 show a specific design of the plastic part to be mounted at the end of the pendulum;

figures 9 to 10 show a specific design of the end of the pendulum;

figure 11 is a view of a product detector according to the invention;

figure 12 is a bottom view of the same product detector;

figure 13 focuses on the added plastic part forming the contact member;

figure 14 shows the detector without this plastic part;

fig. 15 schematically shows a conveyor side wall and a contact member passing the side wall.

Detailed Description

A first object of the invention is a detector 1 for detecting a flow of product on a conveyor 2, comprising:

a base 3 fixed to a side of the conveyor 2,

a pendulum 4 fixed to the base 3 and rotating about an axis 5, said pendulum 4 rotating when the product abuts against it,

a sensor 6 for detecting the position of the pendulum 4.

The conveyor 2 employs the closed belt principle, and the base 3 of the detector 1 is attached to the fixed base structure of the conveyor 2, on which the belt moves. The detector 1 is used to detect the presence or absence of a product in a fixed area. To do this, the detector 1 has a pendulum 4 rotating about an axis 5. The pendulum 4 extends mainly below this axis 5. The product pushes this pendulum 4 and displaces it from the normal stable and balanced position. When the conveyor 2 does not bring the product into the detection zone, the position of the pendulum 4 is defined by its own weight, creating a torque with this axis 5. The position of the pendulum 4 is therefore defined on the one hand by the product itself which is forced against the pendulum 4 and on the other hand by the weight of the pendulum 4. It should be noted that it is contemplated that a force generating member, such as a spring, equalizes the product pressure.

The position of the pendulum 4 in comparison to the base 3 is detected by a sensor 6, the sensor 6 preferably being mounted on the base 3 itself. Preferably based on the principle of metal detection and triggering a signal when the sensor 6 detects metal, which corresponds to a certain position of the pendulum 4: retracted by the product or extended onto the conveying surface by the absence of the product.

The pendulum 4 is fixed to the base 3 outside the product conveying surface, at its top end and at the level of the axis 5. The axis 5 is generally parallel to the conveying direction of the conveyor 2.

According to the invention, the pendulum 4 comprises at its end a contact member 7 having the shape of a flat plate, wherein a non-metallic surface is used for contacting the product, so that the detector 1 can be mounted on a conveyor 2 having a side window 8 of reduced height. This non-metallic surface is preferably made of plastic.

In fact, the bottom end of the pendulum 4 will contact the product. Thus, the pendulum 4 has a contact member 7 at the bottom end. It has longitudinal edges extending in the direction of the conveyor 2, so that transverse forces from the product flow are converted into a pendulum 4 rotation. This contact member 7 preferably also has inclined opposite end portions extending from the longitudinal edges, as best seen in the drawings. The contact member 7 presents such inclined portions at both ends to avoid, in the case of, for example, a pile, the product being trapped between the longitudinal edge and the lateral wall 13 of the conveyor 2 or undetected, in both flow directions, from upstream to downstream normal flow and from downstream to upstream opposite possible return flows.

In the prior art, this contact member 7 is based on a curved rod fixed at the bottom end of the pendulum 4. The present invention differs from the prior art in that the contact member 7 has the shape of a flat and thin plastic piece. The use of a soft plastic material avoids scratching the product and producing noise. The outer surface of the contact member 7 is made of such a soft material. Furthermore, the design of the flat plate provides good stiffness and a limited vertical distance: as will be described in further detail below, the contact members 7 will pass through the side walls 13 of the conveyor 2 and it is important to avoid corresponding passage apertures or windows 8 of higher vertical dimension in said side walls 13.

This design results in a gentle contact with the product, a good stiffness of the pendulum 4, and a restricted corresponding window 8 in the side wall 13.

According to a possible additional feature, the pendulum 4 comprises a support structure 9 and an elongated plastic part 10 mounted at the end of said support structure 9, said elongated plastic part 10 being used to form the contact member 7. The plastic part 10 is made of, for example, ultra-high molecular weight polyethylene. The support structure 9 may be made of metal so as to be easily detected by the sensor 6.

The overall shape of the plastic part 10 is a flat plastic piece extending in a direction parallel to the axis 5, the tapered sides leading to opposite end points once installed. This plastic part 10 forms at least the outer surface of the contact member 7, i.e. the surface that will contact the product. The plastic part 10 preferably also forms the top surface of the contact member 7, as best seen for example in fig. 11.

In some embodiments, the pendulum 4 is formed in one piece, wherein the support structure 9 is integral with the plastic part 10. In some embodiments, the support structure 9 and the plastic part 10 are two distinct parts.

According to another possible additional feature, the plastic part 10 and/or the supporting structure 9 and/or the pendulum 4 are obtained by additive manufacturing (also known as 3D printing). As an alternative to injection moulding, which is also conceivable, the plastic part 10 may thus be obtained by such an additive manufacturing process. The plastic part 10 is subsequently assembled to the support structure 9. The support structure 9 can also be obtained by such a manufacturing process. The entire pendulum 4 can also be formed as a single piece obtained with additive manufacturing.

According to another possible feature, the plastic part 10 has a cavity 11 for receiving a corresponding end of the support structure 9. This cavity 11 is intended to cooperate with the support structure 9, the plastic part 10 being mounted on the support structure 9. In some embodiments, the cavity 11 and the corresponding end of the support structure 9 have complementary elongated shapes, preferably rectangular shapes with overall elongated shape.

As best seen in fig. 14, the support structure 9 has a rectangular longitudinal shaped bottom end extending parallel to the axis 5. A cornered portion may be implemented to connect this longitudinal rectangle to the central arm of the support structure 9. The pendulum 4 is designed such that the support structure 9 and the plastic part 10 have complementary and cooperating geometries: the cavity 11 at the bottom of the plastic part 10 corresponds and fits with the end of the support structure 9, in particular the elongated rectangle. The end of the support structure 9 cooperates with the cavity 11, which contributes to a good positioning.

The plastic part 10 can be fixed to the support structure 9 in a detachable manner. In other embodiments, the plastic part 10 cannot be detached from the support structure 9, for example when using overmoulding, gluing, welding or even a locked snap fit.

Thus, in some preferred embodiments, the plastic part 10 is detachably mounted on the support structure 9. If necessary, the plastic part 10 can then be modified, for example, to be suitable for a processed product, to be removed once worn, soiled or damaged, etc.

In some possible embodiments, the plastic part 10 is screw-mounted to the end of the supporting structure 9. This can be seen, for example, in fig. 11 to 14. Snap-fitting is also a possible embodiment of the removable fixing of the plastic part 10 on the support structure 9.

Moreover, in some possible embodiments, the support structure 9 has an opening 12 that helps to balance the pendulum 4 when the pendulum 4 is forced against the product. As previously explained, at least the weight of the pendulum brings its contact member 7 above the conveying surface of the conveyor 2. Thus, this weight is to be adjusted to ensure that the contact member 7 returns properly in this configuration, but also to avoid over-pushing the pendulum 4 on the product or to avoid too rapid a return movement which would tend to shake the product.

The design of the support structure 9 has an opening 12, preferably at the level of the arm between the contact member 7 and the rotation axis 5.

In the embodiment shown in the figures, the detector 1 will be fixed at the lateral side of the conveyor 2, at the fixed base structure. The products stand on the top surface of this conveyor 2 and are moved by it. The conveyor 2 has a side wall 13 for defining the edge of the product flow. The conveyor 2 is usually of closed-loop design and has a fixed infrastructure on which a motor is mounted for driving the belt.

The detector 1 has a base 3 so that it is fixed to the base structure of the conveyor 2. The detector 1 also has a pendulum 4 that rotates freely about an axis 5. This axis 5 is generally parallel to the direction of the conveyor 2.

Fig. 11 shows that the base 3 has a wheel axle or shaft extending in a horizontal direction in a cantilever manner. The pendulum 4 comprises a complementary hollow tube portion or sleeve to be mounted on said axle. A sensor 6 is also mounted in the base 3 and detects the tab of the pendulum 4, see fig. 11.

It is to be understood that the axis of rotation 5 is located in the top region of the pendulum 4, so that the pendulum 4 can tilt towards said axis 5, wherein the centre of gravity of the pendulum is below said axis 5. At the opposite bottom end, the pendulum 4 has a contact member 7 for contacting the products 2 conveyed by the conveyor 2. This contact member 7 is located at the end of the pendulum 4 and carries the surface on which the product acts.

When the products 2 are on the conveyor 2, they act on the pendulums 4 and rotate them about their axes 5 to reach the retracted position. This means that the end portion of the contact member 7 is pushed by the product to achieve about the level of the side wall 13. The pendulum 4 is in the retracted position. When no product is present or at least far from said side wall 13, the pendulum 4 has a different angular position from the axis 5 and the contact member 7 extends slightly behind the side wall 13, as best seen in fig. 15. The pendulum 4 is normally pushed towards the product by its own weight.

Thus, the contact member 7 will pass the rim defined by the side wall 13. As best seen in fig. 15, the side wall 13 has a window 8 through which the contact member 7 can pass. The window 8 has a size corresponding to the size of the contact member 7 and thus has a reduced vertical height extending in a horizontal direction parallel to the plane of the conveyor 2.

In order to avoid damaging the surface of the product, the contact member 7 has an outer surface made of plastic. Preferably, as seen for example on fig. 11, the contact member 7 has a basic rectangular shape, seen in top view, so as to decrease to two points at its opposite ends. The resulting sloped profile avoids abutment of the product stream either downstream or upstream.

The contact member 7 has the overall form of a blade, that is, a portion having a reduced height compared to the base surface. This blade can thus be moved through the small window 8 in the side wall 13.

The product comes into contact with the contact member at the level of a portion of the periphery of the contact member 7. At least in this part, the contact member 7 is made of plastic.

Preferably, the pendulum 4 has a plastic part 10 at its end for forming the contact member 7. The plastic part 10 extends substantially parallel to the axis 5 and forms the contact member 7.

The plastic part 10 has a reduced height and extends as a flat piece. The plastic part 10 is mounted on the support structure 9 of the pendulum 4, as best seen in fig. 2. This support structure 9 may be metallic in order to facilitate detection by the electromagnetic sensor 6. This support structure 9 ends in a longitudinal rectangular shape. The plastic part 10 at least partially encloses this rectangular shape. As can be seen on fig. 2, the bottom of the rectangular end of the support structure 9 may be free and not covered by the plastic part 10. At least the plastic part 10 is located between the rectangular end of the support structure 9 and the product. The plastic part 10 preferably also completely covers the top of the end of the support structure 9.

Preferably, the ends of the support structure 9 and the plastic part 10 have complementary shapes: the plastic part 10 has a bottom cavity 11 in which an end of the support structure 9 can be received. The cavity 11 and the corresponding part of the support structure 9 have complementary geometries so that the plastic part 10 can have a stable position once fixed to the support structure 9. This geometry includes a rectangle.

The pendulum 4 is therefore made of two different materials: the support structure 9 is made of metal and the plastic part 10 is made of rigid but soft plastic. Thus, the edge of the contact member 7 is soft and does not damage the surface of the product. Furthermore, as previously mentioned, the shape of the blade with limited height also allows the window 8 to have a limited height. The reduced window 8 avoids the circulation of dangerous particles, small products or even dropped products.

For its soft touch properties, the plastic part 10 is preferably made of ultra high molecular weight polyethylene.

In some possible embodiments, the pendulum 4 is formed in a single piece, the plastic part 10 being integral with the support structure 9. The entire pendulum 4 is made of a soft material, such as plastic, to avoid damaging the surface of the product, for example by scratching.

In some particular embodiments, the plastic part 10 is distinct from the support structure 9 and is fixed to said support. The plastic part 10 may be firmly fixed, for example by overmolding, gluing, locked snap-fit, etc. The plastic part 10 may also be removably fixed to the support structure 9, for example by screw mounting or snap fitting or the like. Fig. 1 shows a plastic part 10 which is fixed to a support structure 9 with four screws.

The detachable plastic part 10 makes it possible to replace the plastic part 10 in case of e.g. excessive wear.

As best seen in fig. 4, the support structure 9 has a curved lever: a support structure 9 is mounted to the base 3 at the end of the lever with the contact member 7 at the other end. The weight of this lever helps to bring the contact member 7 onto the conveying surface for detecting the presence of a product. The lever has an opening 12 sized to adjust the weight of the pendulum 4.

While specific embodiments of the invention have been described in detail, it will be appreciated by those skilled in the art that various modifications and alternatives to those details could be developed in light of the overall teachings of the disclosure, in addition to those details discussed above. Accordingly, the particular arrangements disclosed are meant to be illustrative only and not limiting as to the scope of the invention which is to be given the full breadth of the claims appended and any and all equivalents thereof including any and all combinations of their features.

Claims

1. A detector (1) for detecting a product flow on a conveyor (2), comprising:

a base (3) fixed to a side of the conveyor (2),

a pendulum (4) rotationally fixed to the base (3) about an axis (5), the pendulum (4) rotating when a product abuts against the pendulum (4),

a sensor (6) for detecting the position of the pendulum (4),

it is characterized in that the preparation method is characterized in that,

the pendulum (4) comprises at its end a contact member (7), the contact member (7) having the shape of a flat plate with a soft contact surface, having a non-metallic surface for contacting the product, the outer surface of the contact member (7) being made of a soft material, and

wherein the pendulum (4) comprises a support structure (9), the support structure (9) having an opening (12) that helps to balance the pendulum (4) when it is forced against the product.

2. The detector (1) according to claim 1,

the pendulum (4) further comprises an elongated plastic part (10) mounted at the end of the support structure (9) for forming the contact member (7).

3. The detector (1) according to claim 2,

-obtaining the plastic part (10) and/or the support structure (9) and/or the pendulum (4) by additive manufacturing.

4. The detector (1) according to claim 2,

the plastic part (10) has a cavity (11) for receiving a corresponding end of the support structure (9).

5. The detector (1) according to claim 3,

6. Detector (1) according to claim 4, wherein

The cavity (11) and the corresponding end of the support structure (9) have complementary elongated shapes.

7. Detector (1) according to any one of claims 2 to 6,

the plastic part (10) is detachably mounted on the support structure (9).

8. The detector (1) according to claim 7,

the plastic part (10) is screw-mounted to the end of the support structure (9).